The present invention relates to a tray for receiving semiconductor devices, and more specifically, it relates to a tray for receiving semiconductor devices which is injection molded by using conductive plastics.
Recently, miniaturization of semiconductor devices (IC) through large-scale integration is advancing, and they are developing from a pin grid array (PGA) type to a ball grid array (BGA), and furthermore to a land grid array (LGA).
In order to stock and transport these semiconductor devices, specific receiving trays (herein after, simply called tray) are used. These trays are used naturally in order to protect the semiconductor devices in handling, as well as to make handling easier in both manual and automatic loading operations.
Also, in manufacturing of these trays, rapid response to the speed of development of the semiconductor devices is required. Furthermore, in addition to reduction of cost, shortening of delivery period is required.
Numerous trays for housing the aforementioned PGA type, BGA type, and LGA type semiconductor devices have been developed and provided to be adapted to the shapes of the semiconductor devices, and one example is shown in FIG. 11 and FIG. 12. These drawings do not show the entire tray, but rather, they show only one partition for housing one of a large number of arranged semiconductor devices. FIG. 11(a) shows a plan view of this partition, and FIG. 11(b) shows a sectional view taken along line 11(b)xe2x80x9411(b) in FIG. 11(a). FIG. 12(a) shows a sectional view taken along line 12(a)xe2x80x9412(a) in FIG. 11(a), and FIG. 12(b) shows a bottom view of FIG. 11(a). The semiconductor device received in this tray is a BGA type.
This tray overall has a rectangular shape, and supporting parts 101 and 102 are formed horizontally and vertically, that is, with beams in a matrix form, inside a frame (not illustrated) following the external shape of the tray. An open pocket 103 is formed by these supporting parts 101 and 102. On the bottom side of the supporting parts 101, 102, flat strip shaped ribs 101a and 102a are formed to project downwardly therefrom. A semiconductor device 105 is supported at the outer perimeter of the substrate part 105a thereof by the surfaces 101b and 102b on a plane formed by supporting parts 101 and 102 following the perimeter of that pocket 103.
Also, as shown in FIG. 11(b), supporting parts 101c and 102c are formed on the ribs 101a and 102a formed on the bottom sides of the aforementioned the supporting parts 101 and 102, and supporting surfaces 101d and 102d consisting of slopes and planes formed by the tips of these supporting parts 101c and 102c also can support the semiconductor device 105. These supporting surfaces 101d and 102d support the semiconductor devices when the trays are stacked and inverted, and they support an encapsulating resin part 105b of the semiconductor device 105.
A large number of the aforementioned semiconductor devices 105 is received by being mounted on the top side, that is, on the aforementioned supporting surfaces 101a and 102b. Also, other trays are stacked on top of this filled tray and they are placed in a mutually coupled state such that stocking and transporting, and the like, can be performed.
Incidentally, in regard to the aforementioned semiconductor device 105, the work of inspection, and the like, is performed in a state when it is mounted on the aforementioned tray. This inspection work, and the like, is performed not only from the top side of the semiconductor device 105, but also from the bottom side. When performing inspection, and the like, with respect to the top side of the semiconductor device, one may go through the working procedure while maintaining the posture of the tray, that is, with the top side placed upright. On the other hand, when performing inspection, and the like, with respect to the bottom side of the semiconductor device, it is performed in the following manner. That is, the group of trays stacked with the top side placed upright is inverted all together. By this, the semiconductor devices supported on a given tray come to be supported by supporting surfaces 101d and 102d on the bottom side of the tray now being on the lower side (refer to FIG. 11(b)).
By using a tray such as the aforementioned one, the stocking and transporting of the semiconductor devices 105, as well as all kinds of operations with respect to the semiconductor device 105, can be made easier. However, because the aforementioned tray has a large number of ribs in addition to the supporting parts 101 and 102 in matrix form so as to support the semiconductor devices on these beam shaped supporting parts and ribs, and because this tray has acute angular parts, the mold used for molding requires expensive discharge processing, and the like, and it is difficult to reduce the cost.
Also, a tray of such shape has problems such as that it is difficult to make the thickness uniform across the entirety, and warping and buckling tend to occur, and that short shot, which is a phenomenon where the melted resin does not completely spread across, occurs at the fine ribs.
Also, since the outer perimeter of the semiconductor device 105 is supported when performing inspection, and the like, of the top side of the semiconductor device, and the outer perimeter of the encapsulating resin part 105b is supported when performing inspection, and the like, of the bottom side, a considerable difference arises in the two states of support. Specifically, there is a problem that the postures of the semiconductor devices during inspection of the tops and bottoms of the semiconductor devices are not constant, and the postures of the semiconductor devices on the tray may differ at the tops and the bottoms, and when the semiconductor devices are moved by inverting the tray, their postures change. This point is more prominent as the semiconductor devices are smaller.
Furthermore, in considering the handling of a plurality of kinds of the semiconductor devices having the same external shape, according to the conditions of placement of the balls, i.e. contacts, of the semiconductor devices, the tray described previously can handle those where this ball placement part fits inside the aforementioned pocket 103, but it can not be used for those where it doesn""t fit. Also, since the outer perimeter of the encapsulating resin part 105b is supported when supporting the semiconductor devices with the tray inverted, there is a problem that the kinds of the semiconductor devices handled is limited also according to the shape of this encapsulating resin part.
The present invention has been made in consideration of the problems of the aforementioned prior art, and an object of the invention is to provide a tray for receiving semiconductor devices that is of simple constitution and is cheap in cost.
Another object of the invention is to provide a tray for receiving the semiconductor devices as stated above, which prevents deformation, such as warping, and is well-suited for measurement, and the like, from the top and bottom of the semiconductor.
A further object of the invention is to provide a tray for receiving the semiconductor devices as stated above, which can handle many kinds of the semiconductor devices and has high general usability.
Further objects and advantages of the invention will be apparent from the following description of the invention.
In order to achieve the aforementioned objects, the present invention is directed to a tray for receiving semiconductor devices that receives and arranges flat-type semiconductor devices, wherein a plurality of columnar bosses that couple with the outer perimeters of the semiconductor devices is integrally formed on supporting surfaces that support the semiconductor devices so as to surround the semiconductor devices.
Also, in the tray for receiving the semiconductor devices, supporting surfaces that can support the semiconductor devices are provided on top and bottom sides of the tray. A plurality of columnar bosses that couple with the perimeters of the semiconductor devices is integrally formed on the top and bottom side supporting surfaces so as to surround the semiconductor devices. The columnar bosses on the top side of the tray and the columnar bosses on the bottom side are angularly displaced around the centers of the supporting surfaces to be shifted at a specified angular degree.
Furthermore, in the tray for receiving the semiconductor devices, the supporting part with the supporting surfaces on the top side of the tray has a flat plate shape, and the supporting surfaces on the bottom side of the tray are formed on the top ends of frame shaped ribs integrally placed to project outwardly from the bottom side of the flat plate shaped supporting part.
Moreover, in the tray for receiving the semiconductor devices, the columnar bosses on the bottom side of the tray surround the semiconductor devices to form series following the outer perimeters of the semiconductor devices together with the columnar bosses on the top side of the tray when the trays are stacked, and their tips reach into the areas of the tips of the columnar bosses on the top side of the tray.
In addition, in the tray for receiving the semiconductor devices, each columnar boss on the top side and the bottom side of the tray has a conical shape, and the tip is formed in a spherical shape, or the sectional shape in a trapezoidal shape.
Furthermore, in the tray for receiving the semiconductor devices, strip shaped ribs are integrally provided between the frame shaped ribs on the bottom side of the tray.
Also, in the tray for receiving the semiconductor devices, cut-outs are formed at the locations other than the flat plate shaped supporting surfaces.
With the tray for receiving the semiconductor devices, the columnar bosses are located so as to surround the semiconductor device, and position the semiconductor device on a supporting surface.
Also, the supporting surface on the bottom side of the tray is provided in a state such that the columnar bosses on the bottom side are rotated, for example 90 degrees, around the center of the supporting surface with respect to the columnar bosses on the top side, when the trays are in a piled state. Thus, the columnar bosses on the top and bottom become in a mutually adjacent state without interfering with each other. Also, the posture of the semiconductor devices during inspection, and the like, of the tops and bottoms of the semiconductor devices is constant, and inspection of both the top and bottom surfaces can be performed without impediment.
Furthermore, specifically, the supporting part with the supporting surfaces on the top side of the tray is made as a flat plate shape, and the frame shaped ribs are integrally placed to stick out on the bottom surface of this flat plate shaped supporting part. Also, the supporting surfaces on the bottom side of the tray are formed on the top ends of these frame shaped ribs, and the tray substantially is constituted by this flat plate shaped supporting part, the frame shaped ribs, and said columnar bosses. Thus, the structure is simple.
Moreover, the columnar bosses on the bottom side of the tray previously described surround the semiconductor devices to form series following the outer perimeters of the semiconductor devices together with the columnar bosses on the top side of the tray when the trays are stacked, and their tips reach into the areas of the tips of the columnar bosses on the top side of the tray. Thus, in performing inspection, and the like, of the bottom side of the semiconductor devices, when the stacked trays are inverted such that the semiconductor devices move to the tray now being on the lower side, the semiconductor devices move as they are without the occurrence of shifting.
Furthermore, since each columnar boss on the top side and the bottom side of the tray has a conical shape, and the tip is formed in a spherical shape or the tip is formed in a flat conical trapezoidal shape, when the semiconductor device is mounted on the tray, the semiconductor device is smoothly guided to the specified position. The shape of this columnar boss in plan view can be selected as triangular or star shape, or the like.
In addition, the strip shaped ribs provided between the frame shaped ribs on the bottom side of the tray serve as reinforcement, and the rigidity of the tray overall is increased.
Moreover, since the cut-outs are formed at the locations other than the supporting surfaces of the flat plate shaped supporting part, the lightweight tray is made, and handling in transport, and the like, becomes easier.